Fusion effort in flux

Researchers have finished the first phase of an unorthodox, low-cost nuclear fusion experiment that has generated a megawatt's worth of buzz on the Internet – and they are now waiting for a verdict from their federal funders on whether to proceed to the next phase.

Richard Nebel, leader of the research team at EMC2 Fusion in New Mexico, declined to detail the results of the project, saying that was up to the people paying the bills. But he did said "we have had some success" in the effort to reproduce the promising results reported by the late physicist Robert Bussard.

"It's kind of a mix," he said.

The Bussard fusion design, also known as inertial electrostatic confinement or Polywell fusion, is radically different from the multibillion-dollar mainstream approach to the fusion challenge. The idea behind it is that a specially designed high-voltage electrical field can drive ions so closely together that they spark fusion reactions, ideally releasing more energy than the device expends.

In 2005, Bussard said his last test device (named WB-6 because its design was reminiscent of a Wiffle Ball) produced results so promising that he felt he was on the right track toward a breakthrough in low-cost fusion power.

WB-6 was destroyed during the last test run, however, and Bussard struggled to get the funding for a follow-up. He passed away almost a year ago, without building another device, but the Navy provided a reported $1.8 million for Nebel and his colleagues to carry on Bussard's work. Nebel took a leave from his day job at Los Alamos National Laboratory to head the EMC2 Fusion team in Santa Fe.

The team built the WB-7 in an effort to reproduce Bussard's reported results with the WB-6, and to assess whether it was worth scaling up the machine for the next phase of the experiment. Nebel told me that the results of the first-phase test are now being reviewed by the funders and experts in the fusion energy field.

A couple of months ago, Nebel told me that he'd love to ramp up the size of the machine to generate 100 megawatts of electric power. If the technology could actually produce power on that scale, it could offer a quicker route to commercially viable fusion reactors, as well as new propulsion systems for space travel.

When I talked with Nebel last week, he would say only that his team has "a plan to go forward." It's up to the review panel and the funders to give the go-ahead, however. "We don't know whether that's going to happen or not," he told me.

Nebel said his leave from Los Alamos is due to reach the one-year mark in mid-September, but he doesn't foresee any problem in extending the leave if the second-phase funding comes through. Whether or not the Navy funds the next phase, the past year's effort has been worth it, Nebel said. "We're generally happy with what we've been getting out of it, and we've learned a tremendous amount," he said.

All that learning won't go away. "Regardless of what happens to it, we're going to get this thing well written up and documented," Nebel said.

Getting the experiment's findings down on paper will help the EMC2 team - or future teams of fusion researchers - advance the legacy left behind by Bussard. And that's a fitting tribute to the unconventional physicist as the calendar rolls toward the anniversary of his death.

"Bob Bussard was a truly innovative person, that's abundantly clear," Nebel said. "I hope he will be remembered for that. I think that will be the case."